Vintage Gents ORIS Swiss made watch 1960s - 15 Jewels

Vintage Gents ORIS watch Swiss made 1960s 15 Jewels
The champagne dial needs a clean and is stamped "ORIS" and "15".
The hour and minute hands are in good condition and there is a seconds sub-register at 6 o'clock, underneath that the words "Swiss made".
The stainless steel back has words "Lunette Plaque G", "10 Microns" and "Fond acier inox" stamped on it.
The case measures 33mm (without crown) by 39mm.
There is light scratching to the crystal and the case.
The strap is poor quality and should be replaced.
The watch sets and winds but gains time very quickly.